Ants swarm on a plant to eat honeydew left from aphids.

What Can I Put in My Flowers to Kill Ants Without Killing My Flowers?

by Peter Mitchell

Nothing makes flowers look less pretty than an army of ants swarming over the petals. While not every type of ant is harmful to all flowers, some do great damage to the petals in pursuit of nectar. Others cause indirect damage by protecting insects such as aphids - ants feed on the aphids' waste product, honeydew. And if you've got kids, then fire ants or their other stinging cousins can pose a hazard. Thankfully, you don't have to burn your flowers to cinders just to kill a few ants. You have a few simple options for getting rid of the critters.

Citrus oil

Ants don't like citrus oil. In fact, a substance called d-Limonene naturally found in citrus oil kills ants by destroying their breathing system. Yet, citrus doesn't harm plants and is non-toxic for humans. That makes citrus oil a perfect candidate for killing ants without killing your flowers. "Jerry Baker's Bug Off!" suggests mixing 4 cups of orange or lemon peel with 3 gallons of water. This is enough to get rid of an entire fire ant nest. Put the solution it into a vaporizer, and you can spray your flowers to kill any ants, without destroying your beautiful blooms.

Diatomaceous earth

The strangely-named diatomaceous earth is made from fossilized diatoms -- microscopic aquatic creatures. Little did those tiny creatures know that millions of years later their remains could be used to kill ants. The substance has a harsh effect on ant exoskeletons. Just dust some of the diatomaceous earth powder on the soil around your flowers to deter and kill ants, without damaging the plants. You can buy diatomaceous earth from garden stores under a range of different brand names. Always follow pack instructions as although generally non-toxic, if you use too much it can irritate the lungs when inhaled.


Think of your flowers as the castle, and protect them with a moat. By digging a trench around your beloved plants and flowers, you can often prevent those ants from reaching the prize. Fill the trench with citrus water, or water laced with a little vinegar. With smaller house flowers, site the pot in a saucer of water, with a few squirts of citrus for good measure.

Store products

Some products are formulated to kill those darned ants without shrivelling your flowers. For example, products such as Surrender Fire Ant Killer, or Ortho Orthene Fire Ant Killer are marketed as plant-friendly ant pesticides. In both of these cases, you sprinkle the little pellets onto the mound or near active ants during dry weather. They then carry the toxic substance back to the nest where it kills the queen. However, these two brands -- and many others -- contain chemicals that can be harmful to children and pets. So always use with caution and according to pack instructions.

About the Author

Based near London, U.K., Peter Mitchell has been a journalist and copywriter for over eight years. Credits include stories for "The Guardian" and the BBC. Mitchell is an experienced player and coach for basketball and soccer teams, and has written articles on nutrition, health and fitness. He has a First Class Bachelor of Arts (Hons.) from Bristol University.

Photo Credits

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